Zhu Hua, Zhou Yanzi, Xie Daiqian
Department of Chemistry, Sichuan University, Chengdu 610064, China.
J Chem Phys. 2005 Jun 15;122(23):234312. doi: 10.1063/1.1940608.
An ab initio potential-energy surface for the Ne-OCS complex was calculated using the coupled-cluster singles and doubles with noniterative inclusion of connected triples [CCSD(T)] with a large basis set containing bond functions. The interaction energies were obtained by the supermolecular approach with the full counterpoise correction for the basis set superposition error. The CCSD(T) potential was found to have three minima corresponding to the T-shaped and the linear Ne-SCO and Ne-OCS structures. The two-dimensional discrete variable representation method was employed to calculate the rovibrational energy levels for five isotopomers Ne-OCS, (22)Ne-OCS, Ne-OC(34)S, Ne-O(13)CS, and Ne-(18)OCS. The calculated pure rotational transition frequencies for the vibrational ground state of the five isotopomers are in good agreement with the observed values. The corresponding microwave spectra show that the b-type transitions (deltaK(a)=+/-1) are significantly stronger than the a-type transitions (deltaK(a)=0).
使用耦合簇单双激发并非迭代包含连接三重激发 [CCSD(T)] 方法，结合包含键函数的大基组，计算了Ne - OCS复合物的从头算势能面。通过超分子方法并对基组叠加误差进行完全抵消校正来获得相互作用能。发现CCSD(T)势能有三个最小值，分别对应T形以及线性Ne - SCO和Ne - OCS结构。采用二维离散变量表示法计算了五种同位素异构体Ne - OCS、(22)Ne - OCS、Ne - OC(34)S、Ne - O(13)CS和Ne - (18)OCS的振转能级。计算得到的这五种同位素异构体振动基态的纯转动跃迁频率与观测值吻合良好。相应的微波光谱表明，b型跃迁（δK(a)=±1）明显强于a型跃迁（δK(a)=0）。
